Establishment of Ion Chromatography Method for Identification and Determination of the Radiochemical Purity of [11C]Choline Injection

[11C]choline is a normal tracer using for PET/CT，identification of [11C]choline and analysis its radiochemical purity are important to guarantee the validity and safety of tracer. This study aims to establish a new，rapid and effective performance method for identification of [11C]choline and analysis of the radiochemical purity in the products. The chromatographic method of radio-IC-flow-count were performed using a Metrosep C 6-150/4.0 column with mobile phase of 6 mmol/L HNO3+5% acetone aqueous solution，flow rate was 0.9 mL/min. The choline chloride and Na+ retention time were 8.94 min and 3.04 min，[11C]choline were 9.25 min. The established separating method using IC-flow-count showed good efficiency，The linear range of calibration curves was 10–100 mg·L–1 for choline chloride，with the recovery rate ranged from 98.9% to 102.1% and the intrabatch and innerbatch variations of < 7.8%. The radio-IC-flow-count method is simple，valid and quick for the identification of [11C]choline and analysis of radiochemical purity.